Protractor



R. KNUDSEN APRO'LRACTOR Filed March 27, 1945 Sept. 4, A1945.

Ma/wey:

. tells; throughlit the Spcification and drawing.l such end memberis in the form of 4a ,U, 3 I, with ,tomelb'ow portion 3, vwhich asv shown in Figures the U-shaped members yto the positionin. which Patented Sept.` 4, 19,45 s

. 1l r 2,384,100 v i 5.

` rn'o'raao'roa' n Richard Rey Knudsen, Careggi), 5111. l I Apiiaaqn' March 27, mia'seia'lno. 480,744 f' v n i fsclaims.` o1;3 -i'2"1=9)""` y f My invention `relates-itc an improvement in Ir'provideafor example, two thumb nuts I4. which tractors and has Ifor.o r1 e \ol ;lectto provide an imarelscrewv threaded ras `at|5v t-o the member 2 and proved pendulum protractor.y Another object is which have `abutments IBadapted to be urged theproyision'ofaprotractoror angleindicator against the' flange I3..in order to flex them into Whichis adapted, for example, to indicate the de- .51 locking relationship with the flange I 2. .It will be tlection` o f an angle from` a given-,normw observed that there are two of the angesll-one Another object is `the provision of a protractor for each ofthe thumbscrews, I4, .These flanges which may be easily applicable toaugingsureA are separated by slots: I1 from anintermediate Iaces', whether the 4surfaces are generally horiflange I8, which lies-in the same general plane zontalior generally verticalor.departfromboth l as 4the flanges I3 and is ,like them, securedto or horizontal and yertical.. integralwith the memberl2. Thisintermediate Other-.objects will appear from time toV time flange I8 carriesa .forwardlyspaced support or throughout thespecication and claims. bracket I9 which isapertured asat 2Uvto receive `li/Iy. inyention is .-illustrated'fmore or less diathe thumbontrolled rotarypinl I, having a drum grammatically intthe .accompanying drawing, 22 towhich is anchored. a wire. o rycable-r23, the whereini opposite yends of whichare.anchoredasgat24and Figure 1 is a. front elevation with parts broken 25to the housing Aformedbythe members 8, 9 and away;L v Y III. It will be understood that when the ,thumb Figure 2 is a section along the line. 2 2 of Figscrews I4 are released, Vrotation of .the thumb u re l; y 2O controlled pin. 2 I permits movementofthe house- Figure 3 is a section along the line 3-3 of Figing about the center X to anydesiredsettingd ure 1 y. Y i In order to aid in gauging round stock .l pro,-

Lik lDarts aler indicated .by like Characf vide end members at eachend o f the bar I,ea ch Referring` to the drawingIindicates abase bar 25 inwardlyV beveled edges `32 Vand @guiding pin 33 herein shown as angularn cross section-` Secured iixed in the bar I. It will be understood that each to the bar and'upwardly extending fromit is a of the Us slides in the pin33. Eachsuoh Dir-1 lis fa'me'genera-lly indicated as 2. Itincludes a botheaded asat. 34am; a spring `3 5normally urges 2'and` Sfterminates `man angular recessed por- 30 theyare shown in Figures r1 and 2.. Whe'nfthe tionI 4, adaptedto engage yparts o f'two sides of the work is. gauged the U-shaped members maybe .5 indicates any suitable securing means, thrust into the positionshown forexample in Fig-. screws or the. likefor holding the members I and ure 3. Theydo not prevent gauging fiat members 2 together. The Aupwardly extending member 2. is but they' are of `assistance in' gauging round inein- 'provided adjacent anupper portion with anaper- 35 bers as indicated by numeral 30 in Figure'S, Pos';

ture 6. This .aperture serves as a bearingfor a tioned withinthe housing'and in aligmnentwith stud'l rearwardly extending from the rear housthe slot II is an arcuate calibrated member"35" i ing `P11316 3, v"|'heh0ilsir1g plate 1S provided With s hown'as` graduatedl Vto ninetyfdegrees and calia forwardly extending 'side wall 9 extending forbrated tqberea'd on 'eitherend.. ward from its entire circumference. The hous- 40 Concentric'with the stud' land inset in 'the 1 ing iS Completed by any suitable cover plate I0 face of the member 8 is a jewel bearing 40. A which is provided with a circular slot II. The corresponding jewel bearing4| is supported in any slot member, if desired,.may be closed by glass, suitable supporting bridge or bracket or plate 42 plastic, or any suitable transparent material. As which maybe secured as at 43 to the rear memwill be'clear from Figure 1, the contour of the 45 ber or plate 8. lower portion of the housing thus formed is arcu- Mounted in the jewel bearings by penetrating ate, the arc being described about the center X. trunnions 44 is the pivot member 45 shown as A downwardly extending ange I2 extends into generally cylindrical but as partly cut away on the space between the member 2 and the forwardits upper edge as at 46. The cut away portion ly spaced upwardly extending ange I3 herein 50 terminating in an angle located precisely at the shown as unitary with the member 2. center X. The member 45 also carries a pendu- It will be understood that the housing is rotatlum weight 41 which is shown as apertured as at able about the center of the aperture 6, that 48. Supported in the angle 46 by a knife edge center being defined by the point X as shown in 50 is the indicating pendulum 5I which carries a Flaute 1. In ordertolock the housing in position, Vernier scale 52, the edge of which closely apl proaches and is preferably concentric with the upper edge of the scale 35. The pendulum member may include a fork 53 closed by an upper member 54 to which the knife edge member 50 is actually secured. It may for example be inset therein. In order to limit the pendulum in relation to the weight 41, I provide a rearwardly extending pin 55 which penetrates the aperture 48 in the weight. It will be observed that the aperture is of substantially greater diameter than the pin.. vSI1 and 6"! areiabutmentswhich l'iinifttlie movement of the weight and pendulum in relation to the housing. i

'flot The use and operation of my invention are as follows:

In gauging a surface, the bar l' is. applied to@y the surface. The thumb screws I4 are released; i

The thumb control pin 2| is their rotated to '1i move the housing about the center X until one of the zeros of the Vernier is aligned precisely withl the zero of the scale on. the member' 52,

. The housing is; their locked; that position and means for adjusting said. scale in relation to said support, meansffor locking it in. adjusted positiori, and a pendulum mounted' for rotation' about an axis concentric with the axiso-f rotationof said scale; said pendulum having at' its* lower' end an' indicating scale positioned closely adjacent said scale,l and a weightm'oun'ted for limited independent' movementcow-axially with the pendulum# and' a connection b'etweerr` saidl weight and peri-g` dulum adapted to prevent substantial'relative movement. i

2. In a pendulum protractor, a base element' adapted. to be opposed to asurface to be-gauged a support on said base element, air arcuate scale member rotatably adjustable on said support' about acenter remote from' said base'- element, means for adjusting said scalein relation t'ofsaid' support including a manually rotatable". member' and a flexible cable securedx thereto intermediate the ends of the cable; the opposedJ ends' of the' cable being secured to opposed ends' of the scale means forY locking the scale in adjusted position', ari-d'Y a pendulum mounted for rotation*v about an axis concentric with the' axis of rotation ofsaiclj scale, saidV pendulum having anl indicating elenientl positioned closely adjacent the'- scale;

'31 In a pendulum protra'ctor; a lcias'el elementi adapted to be opposedto` a surface'tolegauged,

a support extending from said base element, a pendulum housing mounted on said support for rotary adjustment about a center substantially removed from the base element and from the work contacted thereby, a pendulum in said pendulum housing, rotatable therein about an axis generally concentric with the axis of the pendulum housing, an arcuate scale mounted for move.. ment with said pendulum housing and a scale at the lower endet-said pendulum., opposedy thereto, anda weight.v inl said hdising, mountedior rotation generally concentrically with the pendulum.

4. In a pendulum protractor, a base element adapted to be opposed to a surface to be gauged,

avsupport extending from said base element, a pendulum housing mounted on said support for .rotary adjustment about a center substantially yremoved'from the base element and from the work contacted thereby, a pendulum in said pendulum housing, rotatable therein about an axis generally concentric with the axis ofthe` pendulum housme, an arcuate scale mounted for' movement' with said pendulum housingand a vscale on the lower end of saidA pendulumi opposed theretdanda Weight in said lhousing mounted for rotat'onge'nerally concentrically with; the pendulom,=and means for limiting relative movement of pendulum and weight.

- 5. In; a pendulum protracton' a base elementa support Vextending upwardly, from said base' element, a lsegment shaped housing rotatable on said support about a center' remote from said support, anarcuate calibrated scale mounted-V on and movable with said housing aboutsa'id center, a pendulum mounted for freerotatiom-irr relation to said base and housing, and housed .within the housinaabout a center concentricfwith the center of rotation of the housing, acalibra-ted portion on said pendulum opposed to andimovable in relation to the arcuate 'calibration ofthe 6. In a pendulum protractor, a base element/,la support extending upwardly from said-fbas'elelef ment, a segment shaped-housing rotatable on said supportabout a center remote' from said support, anarcuate calibrated scale mounted on andinovable with said housing about said center',y a peni-i dulum mount'ed'for free rotation, in rel-ationto said basey andhousing, 'and'housed within 'the housing; about a centerconcentric with` the cenL ter of rotation of thev housi-'r-ig, a"calibratedportion on said pendulumjopposed-to and movable in relation to the arcuate' calibration. of the nous?, ing, andan additionalv weight mounted' about the same center as thependulum, and means for'perfmitting slight relativel movement; ofthe pendu-4 lum'and'weight. 'j 'Bronnen Roi: -KNUDsENij f 

